PHILADELPHIA (CBS) — Maj. Bill Cage is in a cage of sorts, one that borders on the inconceivable.

He’s never actually experienced combat. Yet, suddenly, he finds himself on a suicide mission battling aliens. The extra-terrestrial kind. And, sure enough, he is killed in a matter of minutes. Which, of course, is the end of it, right?

Wrong.

Because Cage has been thrown into a seemingly infinite time loop and will live to die again. And again. And at the same place and in the same way.

(3 stars out of 4)

But because he becomes more and more skilled with each pass, he becomes a more effective soldier.

Where he is is on the Edge of Tomorrow, a brutally funny science fiction thriller set in a future in which an imposingly lethal spidery alien race (nicknamed “Mimics” for their ability to mirror our combat strategies) has invaded Earth and taken over most of Western Europe as part of their campaign to wipe out the human race.

Tom Cruise stars as advertising executive Cage, who, despite having no training in combat, is accompanied in his survival efforts by tough Special Forces soldier Rita Vrataski, played by Emily Blunt, whose heroic exploits as the “Angel of Verdun” Cage was originally scheduled to trumpet in a propaganda campaign.

But now they’re both part of a planned surprise assault by the United Defense Force on the coast of France (à la D-Day), which Cage is merely supposed to observe and record with a camera crew, as he has been ordered to do by Gen. Brigham (Brendan Gleeson).

Instead, he finds himself under the command of blustery Sgt. Farrell (Bill Paxton), where he and the others are ambushed by the Mimics, who were obviously aware that the humans were coming. Cage sees Vrataski die and then detonates a bomb that kills both a Mimic and himself.

His death triggers the time loop that he is about to find himself in as he relives the day and the death repeatedly while he issues warnings to the others around him that go unheeded.

And his attempts to somehow save Vrataski’s life fall short.

Will he now have to live out this terrible day repeatedly for all eternity?

Time travel and time loop premises nearly always present problems in internal logic and domino-hitting-domino continuity. But director Doug Liman (The Bourne Identity, Mr. and Mrs. Smith, Jumper, Fair Game), in addition to handling the numerous action sequences adroitly, makes the inherent humor of the situation -– sometimes recalling Bill Murray in Groundhog Day — work for him by having fun with, and getting smiles from, that very conundrum.

There’s plenty of violence, as there must be, but it’s never indulged exploitatively.

There are a surprising number of chuckles in the otherwise serious-minded adapted screenplay by Christopher McQuarrie, Jez Butterworth, and John-Henry Butterworth — based on the 2004 light novel All You Need is Kill, by Hiroshi Sakurazaka -– and the humor certainly helps to leaven the bread in this complicated but clear adventure that often feels like a wall-to-wall action flick.

Needless to say, the editing is crucial here because we are seeing the same event over and over, but editor James Herbert walks the tightrope expertly, never showing us so much as to bore us or so little as to confuse us.

The script offers just enough in the way of exposition for us to follow along. And while the plot contains elements that suggest video gaming, the narrative never collapses into that shallow a showcase.

Both Cruise and Blunt get to tweak their screen personas with this project, with the former offering a self-deprecatingly comedic variation on his well-established leading-man charisma and the latter showcasing herself as a female action star.

Both shine.

Edge of Tomorrow may borrow liberally from other science fiction movies, but it’s a knowing blend of mixed and matched elements that, as it plays out, feels freshly observed and original and unpredictable.

So we’ll live, die, and repeat 3 stars out of 4 for this bracing action-sci-fi cocktail with a comedy chaser.

Calling a movie repetitive is usually a complaint. In the highly entertaining Edge of Tomorrow, it’s merely a plot point.